Toothbrush



'UNITED STATES PATENT GFFICE."

THDMAS HARRISON, Oll "WESTON, ONTARIO, CANADA.

'roo'riannnsrr Application filed March 27, 1920.

T all whom At may concern:

Be it known that I, Tragoiras rlannrson, oli llleston. in the county oi' ll'orlr, Province ol (.lntarioq Canada, have invented certain new and useful lmprovements in Toothlfu.'ushesj oli which the following is a speciication.

My ob] ect in the present invention is to devise a tooth brush that can be talren apart so thatl it may be quickly and thoroughly cleaned. ll attain my object by dividing the bristle carrying head of the brush longitudinally between the rows of bristles and by making the portion of the head carrying an intermediate row of bristles removable. The end of the removable portion is adapted when moved longitudinally of the brush to engage and hold in proper relative position the ends of all the parts of the head. This movement is obtained by the interengagement of the sides of the parts of the head substantially as hereinafter more specifically described and illustrated in the accompanying drawings in Which- Figure l. is a plan vieul of my improved tooth brush looking at the bristle eine thereof. the parts being in position :tor use;

Fig. 2 a similar view showing the parts released ready for the removal of the separable part;

Fig. 3 a side elevation showing the parts in the same position as in Fig. 2;

Fig. l an end view of the brush on an enlarged scale; and

Fig. a cross section on the same scale taken on the line 1a-b in Fig. 1.

In the drawings like numerals of reference indicate corresponding parts in the different iigures.

Tl is the handle oi? the tooth brush, which, as usual, has the head 2 'formed at one end. rlhe head is split longitudinally between the rovvs of bristles on a plurality of planes of division to form an entirely separate intermediate part 3 and a plurality oi outer parts il. The lines of division are preferably ex tended Well into the handle to give sutlicient 4flexibility to the outer members so that they may be sprung apart as indicated in Fig. 2. The separate part lis movable longitudinally of the brush as hereinafter described. and has its outer end `formed with laterally extending hooks 5 adapted to lit over the ends oli' the outer parte lf to loclr them against lateral displacement. It is also pref erable to arrange the hooked end so as to Specification of Letters Patent.

Patented Feb. 1, 1921.

Serial No. 369,309.

prevent displacement of the parts in a direction parallel to the bristles. This is effected by 'lorming grooves 6 in the ends oit' the parts '-.l in which the hooked end 5 may engage as shown. To secure the longitudinal movement ol. the part 3, I provide the sides or 'this part with one or more inclined planes l' adapted to be engaged by a corresponding plane or planes 8 on one or more of the outer parts Il. It is evident that if the part be placed in position and the parts il: pressed together to engage the planes T and 8 that longitudinal movement or the part 3 will be produced as desired. To secure as much lateral movement as possible of the planes il, they are located at some distance from the ends oi? the divisions between the iarts which are remote from the hea-(Lr and. olf course, the planes 7 are correspondingly located. When the parts are pressed together to the position shown in 1 they are held in that position by the slide 9 movable longitudinally of the handle.

(ln the, separate part 3 l prettier to form a button '1.0 by which it may be moved and handled. and which may servo also as a stop to limit the movement of the slide 9 toward the hea d of the brush. lt is evident that at any time by slipping back the slidethat the part l may be removed and that each row oi? bristles is then completely exposed so that the roots of the bristles may be very conveniently and completely cleaned.

lt will be noted on reference to Fig. 5, that the parts 3 and l are shaped on their adjacent sides to interlock to resist displacement. The part 5l will thus remain in place until deliberately pulled out.

lVhat l claim as my invention .is

l. A tooth brush split longitudinally of the bead lzietiveen the bristles on a plurality of lines of division. one part being entirely seljiarated; a booked end on the separated part adapted when moved longitudinally of tlie brush to engage the ends of the other parts to lock them against lateral displacenient; an inclined plane formed on the side of the sepa ate part; and a corresponding plane on the side of one of the adjacent parte adapted to engage the plane on the separate part to draw it longitudinally of the brush to a loclring position.

2. A. tooth brush constructed as set forth in claim l provided with` grooves in the outer parts of the head in which the hooked end of the separate part may engage to pre- Vent displacement of the parts in a direction parallel to the bristles.

3. A tooth brush constructed sV set forth in claim 1 in which the lines of division between the parts are extended into the handle und the inclined planes :iro located intermediate of the ends of the lilies of division :ind :it Considerable distance froin the ends of 10 the lines of division adjacent the handle.

Signed at Toronto, Canada, this 11th day of March, 1920.

THOMAS HARRISON. 

